This invention relates to a transaction processing enclosure wherein the housing or walls, ceiling and floor are formed of a selectively light-weight, composite laminate, adapted for containment of electronic data processing equipment, banking apparatus, and other and related electrical and electronic equipment, and providing thereto a sustained insulated environment substantially immune to impact, for example, from bullets and projectiles, and to flame, smoke and extreme variations in temperature in the atmosphere external to the enclosure.
In general, heretofore, the exterior walls of, for example, buildings have been insulated and loosely packed, bulky materials such as fiberglass, which offer little fire protection. The use of asbestos employed occasionally to insulate girder bars, has abated because of the health hazard it poses. Furthermore, the contact between the surfaces of a building wall and supporting girders has been through direct metal to metal contact using metallic fastening elements such as rivets.
Similarly, conventional interior building walls have been constructed using gypsum (CaSO.sub.4.H.sub.2 O) or similarly low cost mineral material clad in fire resistant papers with a dull finish. More commonly, gypsum board has been used in standard size sheets and attached to intermittantly disposed steel supports, with metal studs driven through the insulating material. These walls are, normally, fabricated however, at the construction site. They are permanent and not readily reusable or relocatable. The gypsum insulating elements have, typically, a density of 2.31-2.33 grams per cubic centimeter, thermal conductivities ranging from 3 to 9 BTU per hour per square foot per degree Fahrenheit per inch thickness, and total emissivity greater than 0.95. The use of conventional metal fastening elements facilitates heat transfer to the supports, as well.
The construction of the fuselage of aircraft, and, more recently, space craft, and the like including wings, where present, and engine compartments has, at the same time undergone a revolution in design over the past several decades resulting in a variety of different structures. Initially, for example, low altitude, low speed aircraft had simple metal skins supported at intervals with a contoured metallic frame. As standard altitudes and speeds have increased, the requirement for maintenance of an ever increasing temperature gradient between the interior and exterior of the craft has also measurably increased. At the same time, simultaneous need for a decrease in weight and an increase in structural strength has resulted in a variety of innovations, centering about two basic structural variations, the "honey comb" design and the composite wall design.
The "honey comb" design refers to the joining of inner and outer wall elements, most commonly metals, using interspersed connection elements, usually metals, fastened using rivets or similar agents. Recently, some adhesives systems have been developed which have had varied success in joining the elements of the skin wall together. However, few can withstand prolonged exposure to temperatures over 200.degree. C. and most bonds formed by the adhesives tend to weaken with vibrational stress and exposure to moisture. Similarly, metal to metal contact is present through the elements of the structure.
The composite walls usually involve the joining of inner and outer metallic layers, with insulating materials disposed between them and supporting structural elements intermittently disposed therein in the form of ribs or struts. The insulating layers have rarely been bonded with success to the metallic layers and have not added significantly to the strength of the wall or skin so formed, in any event. Commonly, the supporting elements are also bound by metal to metal contact using rivets or other suitable fasteners to inner and outer metallic layers. Use of adhesives in this application, to join the metal surfaces and the supporting elements have similar limitations to those described above; that is low thermal resistance, sensitivity to vibration and bond sensitivity to moisture. In most embodiments, the metal to metal contact between the inner and outer layers is reduced but not eliminated.
In a significantly disparate area from that of aircraft fuselage design and construction, the vaults commonly employed to guard currency, other valuables including jewelry, securities, documents of importance and the like, have commonly been bulky structures with relatively thick walls. Most major bank vaults, for example, have concrete walls several inches to several feet in thickness to protect the contents from thermal damage in event of fire and to discourage and hamper forceful entry into the interior thereof by miscreants, vandals, felons and the like.
Ceramic compositions, most desirably, in fiber form, have also been used extensively heretofore as insulating or refractory materials in furnace walls and the like. These compositions may be utilized in randomly distributed fibrous form as well as in embodiments wherein the fibers are linked to form blankets, paper, felt, or fabric. Many ceramic fibers are composites containing varying amounts of silicon oxide (SiO.sub.2) and aluminum oxide or alumina (Al.sub.2 O.sub.3) as well as small amounts of other oxides such as sodium oxide (Na.sub.2 O), boron oxide (B.sub.2 O.sub.3) and iron oxide (Fe.sub.2 O.sub.3). Increasing the alumina content generally increases the thermal resistance of the refractory fiber. The preparation of a refractory glass wool useful as an insulation material and incorporating alumina and silica is disclosed in U.S. Pat. No. 2,557,834. Colloidal silica as a coating cement for graphite, metals and refractories is described in U.S. Pat. No. 3,231,401.
Other ceramic fibrous materials containing chiefly zirconium oxide (ZrO.sub.2) hafnium oxide (HfO.sub.2) and yttrium oxide (YO.sub.2) have also been used as insulating and refractory materials in the various forms recited hereinabove and, indeed, have, generally, superior refractory properties. Thorium oxide (ThO.sub.2) and tantalum oxide (TaO.sub.5), have also been employed for these purposes.
Ceramic fiber forms such as the foregoing are characteristically pliable, and easily folded, cut, or rolled. However, treatment of these ceramic fibrous refractory materials with, illustratively, an aqueous solution containing a concentrated solution of the major component oxide in combination with additional amounts of particulate oxide; evaporation of the water present and drying of the fibers produces a non-pliant or a rigid ceramic fiber form. Solutions such as the foregoing are appropriately termed rigidizers and are well-known to those skilled in the art.
Further illustrating the development in this field, U.S. Pat. No. 3,385,915 recites a procedure to form fibers and articles including a variety of metal oxides; U.S. Pat. No. 3,663,182 recites a method for the formulation of metal oxide-containing fabrics; U.S. Pat. No. 3,860,529 recites means to render ceramic fibers composed mainly of ZrO.sub.2 stable at temperatures of 1000.degree. F. or greater; and U.S. Pat. No. 3,861,947 recites means to render zirconia fibers more thermally resistant by coating them with amorphous silica and reacting the two components.
Ceramic fiber refractory materials have been effectively employed to insulate walls of high temperature furnaces; as linings for molds to accept molten metals, especially aluminum; to protect high temperature components in combustion chambers, such as fuel nozzles; and in applications to seal entry points for cables and conduits entering areas of high temperature such as furnaces and nuclear reactors.
In the foregoing applications the ceramic fiber refractory materials have either been mechanically applied or cemented to surfaces to be protected thereby. Thus, U.S. Pat. No. 3,736,160 describes a fibrous zirconium oxide in a cement matrix containing zirconium oxide and a refractory powder; and U.S. Pat. No. 3,709,717 and U.S. Pat. No. 3,875,971 employ porcelain enamels for bonding zirconium oxide-containing refractory ceramic fibers to metals.
Other developments in the field have centered on containers for temporary storage and transplant of materials requiring maintenance at extremely low temperatures. A material effort in this area has involved improvements in vacuum insulation. Thus, U.S. Pat. Nos. 3,357,586, 3,007,596, and 3,009,600 are directed to the use of composite insulation systems in combination with a vacuum.
U.S. Pat. Nos. 3,108,706 and 2,900,800 deal with the elimination of gaseous hydrogen evolved from the metals forming the double walls of insulation containers and accumulated in the vaccum space provided between the foregoing walls.
At the same time while the refractory ceramic fibers are useful in construction of relatively thin-walled components, as described, illustratively, in U.S. Pat. No. 3,709,710 referred to hereinabove, that are capable of providing effective thermal barriers for many purposes, the load placed on these components is often exceedingly high, however, in that it does not provide for absorption of the radiant heat to which the ceramic fibrous materials are normally exposed. Other intumescent refractory compositions possessed of a low thermal conductivity are also well-known to provide seals for cable penetration through successive floors of buildings and, illustratively, on the interior surfaces of appliances such as hair dryers within a limit source of intermittent heat is present. These refractory intumescent materials are available for use in a variety of compositions including paints, coatings and the like.
It is known to provide closely controlled insulated environments for electronic data processing equipment (other than remotely disposed terminals and the like) by placing all of an organization's data processing equipment in a single large room where overall conditions are maintained substantially uniform, such as referred to hereinabove, and not by use of ceramic fiber panels. The construction of these thick, usually permanent and flame resistant walls is expensive; the location of the equipment is often inconvenient and not adaptable to change even where initially convenient and an accommodation to necessity rather than efficient utilization. A power failure, or the like, will necessitate, in the absence of an auxiliary power supply, a shut-down of an organization's entire electronic data processing system; and in modern terms, where, for example, banks are concerned, will cause closing of the entire business enterprises as well as other enterprises dependent upon it. This vulnerability exists, as well, with sensitive government installations.
The foregoing disadvantages have been overcome to a material degree by the provision of transaction processing enclosures or modules for housing electronic data processing equipment and the like, generally cylindrical in horizontal section, in a particularly preferred embodiment. These readily movable modules or transaction processing centers are described in detail hereinafter and in copending application Ser. No. 952,782 filed Oct. 19, 1978, a divisional application of the U.S. Pat. No. 4,121,523 of one of the applicants herein (and both of which are incorporated by reference herein), but the use of, for example, steel or the like alone in the walls or housing of these modules, while providing an adequate protective means for many purposes, manifests significant disadvantages.
In the event, therefore, that a strong integrated laminate could be devised that would incorporate reduced weight and significant flame and impact resistance and enhanced structural strength under adverse environmental conditions and even at extremely reduced and elevated temperatures and would at the same time prevent, substantially, the passage of radiant and conductive heat, a significant advance in the state of the art would be attained.
Further, if a module or booth could be devised providing containment for one or more units of electronic data processing equipment, banking apparatus, and the like, under which a controlled environment could be assured within the module and under even the most vigorous conditions of temperature and humidity external to the booth, and afford protection against impact and fire while affording structural strength, protection simultaneously, for information, stored for example, on magnetic tape and solid-state elements present in the equipment disposed in the module against the influence of external radio frequency energy and, inded, electromagnetic fields of all frequencies and concentrations, and comply with vigorous governmental requirements in these regards, a further advance of equivalent significant dimensions in the state of the art would be secured.
It is an object of the invention therefore to provide an improved thermal barrier, panel or housing combining low conductivity and high resistance to transfer of radiant heat within an extremely broad temperature range of the order of from about -273.degree. Centigrade(C.) to about 3200.degree. C.
It is an additional object of this invention to provide a light-weight, impact-resistant structurally strong, firmly integrated laminate capable of preventing transmission of both high and low frequency radiant energy in even high concentrations therethrough.
It is a still further and particular object of the present invention to provide a flame retardant, impact-resistant, structurally strong, module or enclosure for incorporation of electronic data processing equipment, electrically or electronically operated banking equipment and the like, including information retrieval systems using magnetic tape and solid state elements or chips that will be protected from either or both high or low radio frequency energy in both high and low concentrations; with maintenance of a desired stable atmosphere within the module or enclosure despite dramatic variations in temperature, relative humidity and the like exterior thereto.
The foregoing and other objectives and advantages of the invention will become more apparent from the description appearing hereinafter in conjunction with the accompanying drawing.